1. Field of the Invention
The present invention relates to a solid-state imaging device in which first and second substrates provided with circuit elements forming each pixel are electrically connected to each other and an imaging device including the solid-state imaging device.
Priority is claimed on Japanese Patent Application No. 2012-184436, filed Aug. 23, 2012, the content of which is incorporated herein by reference.
2. Description of Related Art
In recent years, video cameras, electronic still cameras, and the like have been universally prevalent. In such cameras, a charge coupled device (CCD) type or amplification type solid-state imaging device is used. In the amplification type solid-state imaging device, a signal charge generated and stored by a photoelectric conversion unit of a pixel on which light is incident is guided to an amplification unit installed in the pixel and a signal amplified by the amplification unit is output from the pixel. In the amplification type solid-state imaging device, a plurality of pixels are arrayed in a two-dimensional matrix. An example of the amplification type solid-state imaging device includes a complementary metal oxide semiconductor (CMOS) type solid-state imaging device that uses a CMOS transistor.
A general CMOS type solid-state imaging device uses a method of sequentially reading signal charges generated by photoelectric conversion units of respective pixels arrayed in a two-dimensional matrix form for each row. In this method, an exposure timing in the photoelectric conversion unit of each pixel is determined by the beginning and end of reading the signal charge. Therefore, the exposure timing is different for each row.
A simultaneous imaging function (global shutter function) of realizing simultaneousness of storage of signal charges has been suggested. Further, CMOS type solid-state imaging devices having the global shutter function have been used for various purposes. In the CMOS type solid-state imaging device having the global shutter function, in order to store a signal charge generated by a photoelectric conversion unit is until reading of the signal charge, it is generally necessary to provide a storage capacitor unit having a light-shielding property. In such a CMOS type solid-state imaging device, signal charges generated by the respective photoelectric conversion units are simultaneously transmitted to the photoelectric conversion units in all of the pixels and are temporarily stored after all of the pixels are simultaneously exposed. The signal charges are sequentially converted into pixel signals at predetermined reading timings to be read.
Japanese Unexamined Patent Application, First Publication No. 2010-219339 discloses a method of preventing an increase in a chip area in a solid-state imaging device in which a first substrate provided with photoelectric conversion units is bonded with a second substrate provided with a plurality of MOS transistors.